cachepc-linux

Fork of AMDESE/linux with modifications for CachePC side-channel attack
git clone https://git.sinitax.com/sinitax/cachepc-linux
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imx-iim.c (3071B)

      1// SPDX-License-Identifier: GPL-2.0-only
      2/*
      3 * i.MX IIM driver
      4 *
      5 * Copyright (c) 2017 Pengutronix, Michael Grzeschik <m.grzeschik@pengutronix.de>
      6 *
      7 * Based on the barebox iim driver,
      8 * Copyright (c) 2010 Baruch Siach <baruch@tkos.co.il>,
      9 *	Orex Computed Radiography
     10 */
     11
     12#include <linux/device.h>
     13#include <linux/io.h>
     14#include <linux/module.h>
     15#include <linux/nvmem-provider.h>
     16#include <linux/of.h>
     17#include <linux/of_device.h>
     18#include <linux/platform_device.h>
     19#include <linux/slab.h>
     20#include <linux/clk.h>
     21
     22#define IIM_BANK_BASE(n)	(0x800 + 0x400 * (n))
     23
     24struct imx_iim_drvdata {
     25	unsigned int nregs;
     26};
     27
     28struct iim_priv {
     29	void __iomem *base;
     30	struct clk *clk;
     31};
     32
     33static int imx_iim_read(void *context, unsigned int offset,
     34			  void *buf, size_t bytes)
     35{
     36	struct iim_priv *iim = context;
     37	int i, ret;
     38	u8 *buf8 = buf;
     39
     40	ret = clk_prepare_enable(iim->clk);
     41	if (ret)
     42		return ret;
     43
     44	for (i = offset; i < offset + bytes; i++) {
     45		int bank = i >> 5;
     46		int reg = i & 0x1f;
     47
     48		*buf8++ = readl(iim->base + IIM_BANK_BASE(bank) + reg * 4);
     49	}
     50
     51	clk_disable_unprepare(iim->clk);
     52
     53	return 0;
     54}
     55
     56static struct imx_iim_drvdata imx27_drvdata = {
     57	.nregs = 2 * 32,
     58};
     59
     60static struct imx_iim_drvdata imx25_imx31_imx35_drvdata = {
     61	.nregs = 3 * 32,
     62};
     63
     64static struct imx_iim_drvdata imx51_drvdata = {
     65	.nregs = 4 * 32,
     66};
     67
     68static struct imx_iim_drvdata imx53_drvdata = {
     69	.nregs = 4 * 32 + 16,
     70};
     71
     72static const struct of_device_id imx_iim_dt_ids[] = {
     73	{
     74		.compatible = "fsl,imx25-iim",
     75		.data = &imx25_imx31_imx35_drvdata,
     76	}, {
     77		.compatible = "fsl,imx27-iim",
     78		.data = &imx27_drvdata,
     79	}, {
     80		.compatible = "fsl,imx31-iim",
     81		.data = &imx25_imx31_imx35_drvdata,
     82	}, {
     83		.compatible = "fsl,imx35-iim",
     84		.data = &imx25_imx31_imx35_drvdata,
     85	}, {
     86		.compatible = "fsl,imx51-iim",
     87		.data = &imx51_drvdata,
     88	}, {
     89		.compatible = "fsl,imx53-iim",
     90		.data = &imx53_drvdata,
     91	}, {
     92		/* sentinel */
     93	},
     94};
     95MODULE_DEVICE_TABLE(of, imx_iim_dt_ids);
     96
     97static int imx_iim_probe(struct platform_device *pdev)
     98{
     99	struct device *dev = &pdev->dev;
    100	struct iim_priv *iim;
    101	struct nvmem_device *nvmem;
    102	struct nvmem_config cfg = {};
    103	const struct imx_iim_drvdata *drvdata = NULL;
    104
    105	iim = devm_kzalloc(dev, sizeof(*iim), GFP_KERNEL);
    106	if (!iim)
    107		return -ENOMEM;
    108
    109	iim->base = devm_platform_ioremap_resource(pdev, 0);
    110	if (IS_ERR(iim->base))
    111		return PTR_ERR(iim->base);
    112
    113	drvdata = of_device_get_match_data(&pdev->dev);
    114
    115	iim->clk = devm_clk_get(dev, NULL);
    116	if (IS_ERR(iim->clk))
    117		return PTR_ERR(iim->clk);
    118
    119	cfg.name = "imx-iim",
    120	cfg.read_only = true,
    121	cfg.word_size = 1,
    122	cfg.stride = 1,
    123	cfg.reg_read = imx_iim_read,
    124	cfg.dev = dev;
    125	cfg.size = drvdata->nregs;
    126	cfg.priv = iim;
    127
    128	nvmem = devm_nvmem_register(dev, &cfg);
    129
    130	return PTR_ERR_OR_ZERO(nvmem);
    131}
    132
    133static struct platform_driver imx_iim_driver = {
    134	.probe	= imx_iim_probe,
    135	.driver = {
    136		.name	= "imx-iim",
    137		.of_match_table = imx_iim_dt_ids,
    138	},
    139};
    140module_platform_driver(imx_iim_driver);
    141
    142MODULE_AUTHOR("Michael Grzeschik <m.grzeschik@pengutronix.de>");
    143MODULE_DESCRIPTION("i.MX IIM driver");
    144MODULE_LICENSE("GPL v2");